COLUMBIA, S.C. — Republican White House hopeful John McCain's support for a bipartisan immigration bill has cost him the backing of a South Carolina county campaign chairman.

David Nix, who had been heading the Aiken County campaign for McCain, told McCain press secretary Adam Temple that he was quitting as county chairman because of the immigration bill, which some critics have decried as providing amnesty for illegal aliens.

Nix's e-mailed resignation Wednesday came in response to an e-mail from Temple about McCain's Tuesday night debate performance.

"As most of you saw last night, Senator McCain did extremely well last night," Temple wrote. He asked McCain's county chairmen to call into radio shows to talk up McCain and his agenda.

Nix, who served as the county GOP chairman from 2000-2004, responded with a brief note. "Please consider this my resignation as Aiken County chair for McCain. I am too far from him on the Amnesty Bill. I was hopeful that he could keep his nose clean this time around, but he can't read the pulse of the American citizens," he wrote.

Nix did not respond to a message left seeking comment. McCain's South Carolina campaign spokesman, B.J. Boling, confirmed the contents of the e-mail.

Attorney General Henry McMaster, McCain's South Carolina campaign co-chairman, said McCain won't have agreement from any leader on every issue. He noted McCain has 80 county chairs and co-chairs and hundreds of other endorsements.

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